for 5. i ended up with (x (7x^3 -5x^2-37x-35))/(x^4+5x^2-6) = 0..but that doesn't seem right
in 14 and 15 i don't know what the triangles mean
I have never graphed functions with restrictions like in 16 and 17
i think 13a. doesn't have a domain
i don't know what the symbols in 41-43 stand for